Classification primitives become ready when show is false

[bagnell]

Ground and classification primitives will become ready when show is false. For #6413.

CC @mramato @hpinkos The tests fail in master from timing out. Is there a better test?

[cesium-concierge]

@bagnell, thanks for the pull request! Maintainers, we have a signed CLA from @bagnell, so you can review this at any time.

⚠️ I noticed that CHANGES.md has not been updated. If this change updates the public API in any way, fixes a bug, or makes any non-trivial update, please add a bullet point to CHANGES.md and comment on this pull request so we know it was updated. For more info, see the Pull Request Guidelines.

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[hpinkos]

This looks good to me! And this should allow @roderickgreen to finish his flickering polygons pull request.

@mramato did you want to take a quick look at this?

[mramato]

This is fine with me, I merged in master so as soon as this is green someone can hit merge.

[mramato]

Thanks @bagnell